PHYS.—But there are surely other species of salmon, that live in the sea and come into our rivers: I have heard of fish called _grays_, _bull trout_, _scurfs_, _morts_, _peales_, and _whitlings_. HAL.—I have never been able to identify more than the _salmo salar_, or salmon, and _salmo trutta_, or sea trout, in the rivers of Britain and Ireland. The whitlings I believe to be the young of the sea trout. A sea trout which I saw in Ireland, called a bull trout, was of the same kind as these you see here, but fresh water trout are sometimes carried in floods to the sea, and come back larger and altered in colour and form, and are then mistaken for new species: and as each river possesses a peculiar variety belonging to it, this, with differences depending upon food and size, will, I think, account for the peculiarities of particular fish, without the necessity of supposing them distinct species. I remember many years ago, the first time I ever fished for salmon in spring in the Tweed, I caught with the fly, one fine morning in March, two fish nearly of the same length: one was a male of the last season, that had lost its melt; the other a female fresh from the sea. They were so unlike, that they did not appear of the same species: the spent or kipper salmon was long and lean, showing an immense head, spotted all over with black and brown spots, and the belly almost black; the other bright and silvery, without spots, and the head small. Even the pectoral and anal fins had more spines in the newly run fish, some of the smaller ones having been probably rubbed off in spawning by the other. I would not for some time, till assured by an experienced fisherman, believe, that the spent fish was a salmon; and when their flesh was compared on the table, one was white, flabby, and bad, and without curd; the other of the brightest pink, and full of dense curd. Then, though of the same length, one weighed only 4lbs., the other 9½lbs. When it is recollected, that different salmon and sea trout spawn at different times in the same river, and that fish of the same year, being born at different seasons, from Christmas to Lady-day,—and having migrated to the sea in spring—run up the rivers of all sizes in summer and autumn—the young salmon from 2 to 10lbs. in weight, the young sea trout from ½ to 3lbs. in weight—it is not difficult to account for the variety of names given by casual observers to individuals of these two species. But I must not forget my promise of sending a fish to the Highlander, with whose sport we have interfered. There is a good salmon, which shall be taken to him immediately, and for which I shall pay the taxman his usual price of 5_d._ per pound. FIFTH DAY. HALIEUS—POIETES—ORNITHER—PHYSICUS. MORNING. HAL.—WELL, is your tackle all ready? It is a fine fresh and cloudy morning, with a gentle breeze—a day made for salmon fishing.